Centennial Honors College
Western Illinois University
Undergraduate Research Day 2012
Poster Presentation
Vertically Transmitted Endophytes Isolated From Plants in the Alpine Tundra
Poster Presentation
Antonio Rosales and Katrina Sandona
Faculty Mentor: Andrea Porras-Alfaro
Biology
Alpine tundra plants are able to survive harsh conditions with the help of endophytes
and mycorrhizal fungi. Endophytes are fungi or bacteria that live within plants without
causing apparent damage. These symbiotic relationships between plants and
endophytic fungi are known to have a direct impact on plant community structure,
fitness, and diversity. Endophytes can colonize plants by either horizontal or vertical
transmission and little is known about their abundance, taxonomy and function. The
objective of this study was to isolate and quantify vertically transmitted endophytes from
plant seeds that were collected at the Niwot LTER Site in Colorado. Six plant species
(Geum rossii, Erigeron simplex, Artemisia scopulorum, Deschampsia cespitosa, Bistorta
bistortoides, and Trisetum spicatum) were studied. Thirty seeds of each plant were
surface sterilized and plated on malt extract agar with antibiotics. Fungi were
sequenced using the ITS rDNA region. Thirty three endophytes were isolated from the
seeds. Ten different morphotypes were present. E. simplex and D. cespitosa show the
highest germination rates. Germination rates varied between 67% to 0% and
colonization rates varied between 6% to 33%. B. bistortoides seeds did not germinate
and showed the highest fungal colonization rates. Preliminary identification of some
isolates using ITS rDNA shows that G. rossii and D. caespitosa seeds are colonized by
a fungus closely related to Cladosporium uredinicola. Additional tests need to be
conducted to determine the potential role that these seed endophytes may have in plant
germination, seed establishment and the structure of plant communities in the alpine
tundra.